The eunuchs in Korea’s royal court of the Chosun Dynasty lived considerably longer than “intact” men, researchers reported in the journal Current Biology. The study appears to confirm what previous animal studies have shown – that castration prolongs life expectancy.

The Chosun Dynasty ran from 1392 to 1910. During this period, some boys were castrated and became servants in the royal palace. The researchers found that their life spans were from 14 to 19 years longer than those of non-castrated men.

The Chosun court eunuchs, unlike their counterparts across Asia and the Middle East, could get married if they wanted to and adopt children.

The Korean eunuchs had privileged positions and lifestyles. However, authors Kyung-Jin Min and Cheol-Koo Lee believe their longer lifespans were due to some additional factors, apart from good nutrition and socio-economic status. The authors explained that while eunuchs clearly lived longer than other males, it is not possible to put this down solely to their lack of testicles.

Most experts agree that a person’s genes have a major impact on how long they are likely to live. A study carried out by experts from Albert Einstein College of Medicine of Yeshiva University revealed in the Journal of the American Geriatrics Society that genes are much more important than lifestyle in determining lifespan.

Kyung-Jin Min explained to Reuters that the vast majority of the Korean eunuchs lived outside the royal court and only went in to work.

The monarchs lived an average of 47 years, compared to the 70 years enjoyed by their castrated servants.

Of the 81 eunuchs the researchers studied, three lived over 100 years, giving them a130-times greater chance of becoming centenarians than in countries today with the longest life expectancies.

Several studies have shown that in the animal kingdom, female mammals tend to live longer than males. Researchers believe that testosterone, which exists in much higher levels in males, possibly undermines the immune system and raises the risk of cardiovascular diseases.

Written by Christian Nordqvist